The present invention relates to a resistance element referred to as a “variable resistance functional body” whose electrical resistance changes between before and after application of a voltage and a manufacturing method therefor. This invention also relates to a storage device provided with such the variable resistance functional body.
In recent years, there have been proposed memory devices (single electron transistor and single electron memory) which are each provided with a nanometer-size particle called a nanodot and a nanocrystal in an insulator in order to store information through the use of, for example, a charge storage effect (refer to a patent document JP 2000-22005 A).
However, the memory devices of this kind require very fine processing in order to produce a nanosize dot capable of storing one or several electrons and to detect the flow of several electrons. The very fine processing makes it difficult to integrate them. Moreover, it has often been required to provide an extremely low temperature in order to restrain the occurrence of malfunction due to thermal fluctuation. For the above reasons, the memory devices that employ nanosize dots have poor practicability and still remain at the experimental level.
Moreover, in forming many nanodots, it is required to repeat same processes many times by using the CVD (Chemical Vapor Deposition) method or to grow particles by using the thermal annealing method. However, the particles formed by using those methods also have such problems that the particles have poor thermal stability and often have characteristics hardly applicable to normal silicon processes.
On the other hand, there has not yet been known a resistance element in which many conductive particles are produced at a time and the conductive particles are nanosize particles (nanodots) excellent in thermal stability.